<template>
  <div>hello {{world}}--{{ counter }} 秒</div>
</template>
<style scoped>
</style>
<script>
  export default {
    name: 'HelloWorld',
    data() {
      return {
        world: '',counter:0
      };
    },
      created: function () {
        var vm = this
        setInterval(function () {
          vm.counter += 1
        }, 1000)
      }
  }
</script>